a) Field of the Invention
The invention relates to an arrangement with a motor unit, with a pump unit which is in a driving connection with the motor unit and generates a water jet, and with fastening members for detachably mounting the arrangement to a watercraft, particularly an inflatable boat.
b) Background of the Related Art
It is known to produce hydraulic jet-drive mechanisms for watercraft as complete structural units, to arrange them on the suitably constructed watercraft and to couple them with a motor unit arranged in the watercraft (compare DE-OS 21 52 308).
However, for this purpose the watercraft must have a portion constructed as an inlet duct for the water which is to be sucked in so that boats of standard construction from conventional series manufacture are not suitable for mounting such drive arrangements. This is particularly true of inflatable boats which are produced from material which is pliable in bending and maintains its dimensional stability by means of enclosed air at above-atmospheric pressure and which have only a lower stern or transom produced from solid material, e.g. wood or metal.
For this reason, inflatable boats formerly had to be provided in particular with stern parts which were rigid in themselves and whose construction enabled the mounting and fastening of this stern part on the end of the hull of the inflatable boat (compare Hobby, 1974, page 10, "Hydro-Dyn").
Apart from the fact that they are expensive to produce, such stern parts are bulky and difficult to transport in view of their space requirement.
Based on the known construction of so-called Z-type drives in which the motor and screw are allocated to a common shaft housing and which can be mounted on the transom of a watercraft of any construction simply by means of a screw connection, the invention has the object of providing an arrangement for propelling a watercraft, particularly for an inflatable boat made from structural component parts occupying little space so as to economize on weight. This arrangement is constructed as a mount-on unit enabling a secure support of the motor unit and a pump which generates a water jet and whose construction and arrangement enable mounting by untrained water-sports enthusiasts.
This object is met according to the invention in that the motor unit and pump unit are allocated to the opposing surfaces of the front side of a housing which partially encloses at least the pump housing, the front side of the housing being penetrated by the driving connection between the motor unit and pump unit and by supporting members which are rigidly connected with the housing and serve to support the motor unit, and the front side of the housing is constructed as a fastening flange of the arrangement for mounting to the transom of the watercraft.
According to a further feature of the invention, the housing is made from plates which are detachably connected with one another and the supporting members are constructed as rods which are detachably fastened at the plates forming the opposing side faces of the housing, the supporting members enclosing an angle diverging from 90.degree. with the front side of the housing penetrated by them.
According to a preferred embodiment form of the invention, the supporting members are arranged parallel to the power train between the motor unit and pump unit.